Question

4. An airplane at T(80,20) needs to fly to both U(20,60) and V(110,85). What is the shortest possible distance for the trip?

Answer 1

The distance formula for two points in a plane is 
D=sqrt( (x1-x2)^2 + (y1-y2)^2 ) 
 From T to U
 D= sqrt((80-20)^2 + (20-60)^2) = 72.11 
 Then flying from U to V
 D= sqrt((20-110)^2 + (60-85)^2) = 93.4 
 So T to U to V = 72.11+93.4 = 165.5 
 BUT checking also T to V to U
 From T to V
 D= sqrt((80-110)^2 + (20-85)^2) = 71.6
 Then from V to U
 D= sqrt((110-20)^2 + (85-60)^2) = 93.4 
 So from T to V to U = 165
 Pretty much the same both directions
 So yes the answer is A